1. Field of the Invention
The present invention relates to an arrangement for aligning a semiconductor process tool to a track system, and to a method which facilitates the calibration and alignment between a previously installed overhead transport system in a fabrication facility or plant for semiconductor wafers or integrated circuit components, and a plurality of load ports on a process tool for the semiconductor wafer or integrated circuit components, which is to be subsequently installed in the fabrication facility.
The concept of providing methods and arrangement for aligning a load port on a process machine or tool employed in the fabrication of various products, such as semiconductor wafers or integrated circuit components in a highly precisely aligned manner is widely known and employed in the applicable technology. In this connection, in many instances the overhead transportation systems utilized for the delivery of the components, which are to be processed, are installed subsequent to the positioning of the processing tool, which has been previously installed in the facility.
Generally, semiconductor fabricating equipment, which is provided for industrial fabrication installations (FABs), necessitate the provision of a large number of diverse processing or treatment chambers, modules, load ports and auxiliary equipment, which are assembled and fastened together in order to collectively form an equipment body, which is generally designated as a process tool. The particular process tool for the treatment of the semiconductor wafers or integrated circuit components is then operatively correlated in the fabrication facility with a number of mechanical connections which are provided for the supplying of process gasses, water, electrical power, HVAC, vacuum and exhaust, wherein the completed process tool assembly may be of a large and bulky size and processed of a weight in excess of several thousand pounds of assembled equipment and connections. Consequently, in the event that the orientation of the process tool equipment prior to assembly and installation in the fabrication facility is not correctly aligned with respect to the previously installed overhead track or transportation system which has been mounted in the fabrication facility, the integrity of the entire project in effecting the processing of the wafers is rendered doubtful in nature, and may necessitate the implementing of complex and costly modifications and production downtime in attempting to correct any misalignments which is present between the overhead track or transportation system and the process tool which is employed for the processing of the semiconductor wafers or integrated circuit chips.
Although installations and methods are currently known and employed in the technology for the alignment, and essentially optical alignment, between a FOUP load port of a process tool or wafer treating apparatus and an overhead transport system, this is generally implemented in that the overhead transport system is installed subsequently to the process tool, and thereafter, the load port on the process tool is aligned with the transport system. This is, essentially, a method of a nature which is subject to the problems as set forth hereinabove.
2. Discussion of the Prior Art
The publication of International SEMATECH, entitled “Guidelines for the Installation and Alignment of 300 mm Overhead Transports Systems (OTS) and Load Port Interfaces”, Technology Transfer No. 02064276A-ENG, dated Jun. 19, 2002, discloses guidelines for the processing of 300 mm semiconductor wafers for integrated circuits, which pertains to the installation of a process equipment in alignment with an overhead transport system subsequent to the process tool being mounted in place in a fabrication facility. However, there is no disclosure of enabling such process tools, which posses multiple FOUP load ports to be aligned with a previously installed overhead transportation system in a manner analogous with the present invention, the latter of which employs a novel laser alignment apparatus for determining the accurate positioning of a process tool with a previously installed overhead transportation system.
The problem is also addressed in Lin, et al., U.S. Pat. No. 6,541,787 B2, which relates to the disclosure of an apparatus and a method for aligning a load port on a process tool or machine for 300 mm semiconductor wafers with an overhead transportation system. Again, although there is provided for an interface between a load port or a FOUP port, in effect a front opening unified port holding a plurality of 300 mm semiconductor wafers, does not this enable or disclose the alignment in a dynamic manner of a plurality of load ports on process tool installations relative to a previously installed overhead transport system employed in the fabrication facility.
Similar limitations in providing accurate alignments between process tools for semiconductor wafers and overhead transportation systems are encountered in the technology as represented by the disclosures of Schauer, et al., U.S. Patent Publication No. 2003/0083776 A1; Huang, et al., U.S. Patent Publication No. 2002/0197136 A1; Hsiao, U.S. Pat. No. 6,546,307 B1; Kovac, U.S. Pat. No. 6,433,875 B1; Palumbo, II, U.S. Pat. No. 6,286,219 B1; Slater, et al., U.S. Pat. No. 6,034,763; Krolak, et al., U.S. Pat. No. 4,615,615; and Brad Chen, German Patent Publication No. DE10033817 A1.
The prior art publications which are currently representative of the technology concerned with semiconductor manufacture and particularly in implementing precision alignment between an overhead track and a FOUP load port and kinematic load port interface fail to solve the problems encountered in the alignment between the locations of large scale and heavy semiconductor equipment or process tools and overhead track or transportation systems.